Attenborough and the Giant Elephant (2017) Timeline Explained – Every Event in Order

A Shepherd Makes a Sensational Discovery

A shepherd working at La Flecha Farm in Chubut Province, Patagonia, stumbles upon a massive fossilised femur, or thigh bone, exposed in the ground. The find is the first evidence of a colossal new species of titanosaur, a long-necked plant-eating sauropod from the Cretaceous period. The enormous bone immediately hints at an animal of extraordinary proportions.

Where

La Flecha Farm, Chubut Province, Patagonia, Argentina

The Excavation Begins

Specialists from the Museum of Paleontology Egidio Feruglio in Trelew travel to the site under the direction of Dr Diego Pol and Dr José Luis Carballido. Over the next two years they carefully excavate some 220 bones from the ground. At first the team assumes all the remains belong to a single individual, but the dig will eventually reveal a far more remarkable story.

When

Over a period of two years

Where

La Flecha Farm, Chubut Province, Patagonia, Argentina

Wrapping and Hauling Out the Giants

Each excavated bone is stabilised with wet toilet paper and encased in plaster of Paris to protect it from damage. A specially constructed road is then built so the heavy, plaster-jacketed fossils can be hauled out of the site. This painstaking logistics work keeps the fragile fossils intact on their journey from the field.

Where

La Flecha excavation site, Chubut Province, Patagonia, Argentina

Freeing and Scanning the Fossils

At the museum, preparators slowly remove the bones from their surrounding rock matrix, revealing the fine detail of each fossil. An international team of skeleton builders then 3D-scans every prepared bone. The digital data captures the exact shape and size of the skeleton, forming the foundation for everything that follows.

Where

Museum of Paleontology Egidio Feruglio, Trelew, Patagonia, Argentina

A Life-Size Replica Takes Shape

Using the 3D scan data, a life-size replica of the titanosaur is built in Toronto, Canada, with fibreglass cast in computer-cut polystyrene moulds. Piece by piece, the gigantic skeleton is assembled, bone by bone. Seeing the full-sized mount gives the scientists their first true sense of the animal's staggering scale.

Where

Toronto, Canada

Reconstructing the Missing Head

By the end of the filming period no skull has been recovered, so the model's head has to be reconstructed from the most likely of the three known titanosaur skulls. The choice is guided by the single titanosaur tooth found at the site. Dr Pol explains that titanosaur skulls rarely survive as fossils because they were delicate bones with light sutures.

Where

Toronto, Canada

Measuring a Record-Breaking Animal

One of the recovered femurs measures 2.4 metres long, and a humerus has a circumference of 79 cm at the centre of the shaft. From these measurements the team estimates the animal at 37 metres long and around 70 metric tons in weight. The figures suggest a titanosaur even bigger than Argentinosaurus, previously the largest known species of its kind.

A New Species Is Confirmed

A ridge on the back of one of the vertebrae, together with a few other distinctive anatomical features, convinces the team that the bones belong to a species new to science. The dinosaur is not formally named in the programme, but it is later scientifically described as Patagotitan mayorum in 2017. The find cements Patagonia's reputation as a land of prehistoric giants.

Dating the Titan and Rebuilding Its World

Volcanic ash found around the bones dates the animal to 101.6 million years old. The titanosaurs would have fed on cycads, ferns and conifers, all fibrous, hard-to-digest and low-nutrient foods. The towering monkey puzzle tree, a living descendant of those conifers, still grows over 40 metres tall at the foot of the Andes, a height only a long-necked titanosaur could reach.

When

101.6 million years ago

Where

Patagonia, Argentina

Clues to Life and Death at the Site

More than 80 teeth of the carnivorous carcharodontosaurid Tyrannotitan chubutensis are recovered from the site, and one titanosaur tail vertebra bears marks this giant hunter may have made, either through scavenging or hunting. In total, 223 bones from seven different individuals lie on three separate levels, indicating three distinct occasions on which animals were deposited there. Possible explanations include animals dying at water pools that dried up, rivers that were too small to wash the bodies to the site, and nearby volcanic eruptions that killed the animals or destroyed the vegetation they fed on.

Where

La Flecha excavation site, Chubut Province, Patagonia, Argentina

The World's Largest Dinosaur Nesting Ground

Attenborough travels to Auca Mahuevo, 800 kilometres north of the titanosaur site, the largest known dinosaur nesting ground in the world. Nests full of eggs stretch across several kilometres, and he struggles to walk without stepping on them. He discusses the site with one of its discoverers, Dr Luis Chiappe, and four separate layers of eggs show that the dinosaurs returned there again and again.

Where

Auca Mahuevo, Patagonia, Argentina

A Peek Inside a Dinosaur Egg

At the Museo Carmen Funes in Plaza Huincul, Neuquén Province, Attenborough examines a fossil egg from the nesting site that contains mineralised baby dinosaur skin. Other eggs from Auca Mahuevo preserve limb bones and even skulls of unhatched youngsters. These extraordinary fossils offer an intimate glimpse into the earliest stages of titanosaur life.

Where

Museo Carmen Funes, Plaza Huincul, Neuquén Province, Argentina

Learning from the Largest Land Animals Today

At Whipsnade Zoo in Bedfordshire, England, Professor John Hutchinson studies the gait of elephants, the largest living land animals, to shed light on how the titanosaur might have moved. He also calculates that the titanosaur's heart would have had a circumference of some 2 metres. Attenborough additionally watches giraffes to see how such a long neck allows grazing on foliage high in the trees.

Where

Whipsnade Zoo, Bedfordshire, England

Putting the Skeleton on Its Feet

The 3D data behind the replica is also turned into a computer model, allowing scientists to study the titanosaur's posture and gait. Ben Garrod joins the team in Argentina to help work out how the enormous skeleton would have walked. Komodo dragons provide a living illustration of how the titanosaur might have used its heavy tail.

Where

Patagonia, Argentina

Bigger Than Argentinosaurus

The finished replica reveals that the dinosaur was still not fully grown when it died, meaning the living adults would have been even larger. The team concludes the species was roughly 10% larger than Argentinosaurus, making it one of the biggest land animals ever to have walked the Earth. The farm's owner, Alba Mayo, sums up the local astonishment: 'I don't have many sheep, but I do have dinosaurs!'